In situ repair of mechanical failure remains a largely unexamined area of study in biomaterials. A newly emerging area of materials science is Self-Healing Materials (SHM) that uses a variety of embedded chemistries to detect and repair microcracks in situ before they coalesce into propagating cracks. This R21 proposal examines the feasibility of incorporating biocompatible, non-toxic SHM technology into one of the simplest load-bearing biomaterial formulations -- two component acrylic bone cement -- with the most straightforward SHM technology -- microencapsulated healing agent dispersed in a catalyst-embedded polymer matrix. The study consists of four specific aims. Aim 1: Fabrication of microencapsulated alkyl cyanoacrylate healing agent using emulsified oil in water interfacial polymerization. Aim 2: Incorporation of the icroencapsulated healing agent into the two-component PMMA matrix. Aim 3: Characterization of self-healing bone cement mechanical properties and fracture mechanics. Aim 4: Cytotoxicity testing of self-healing bone cement by elution testing of extraction media in mouse fibroblast culture, and by cell ongrowth onto samples of bone cement placed in cultures of human osteoblasts.